Mixtures of esters of sulfosuccinic acid



United States Patent 3,043,706 MIXTURES F ESTERS 0F SULFOSUCCINIC ACIDWilliam Simeon Fair and Kenneth D. Rallou, Charlotte, N .C., assignorsto American Cyanamid Company, New York, N.Y., a corporation of Maine NoDrawing. Filed Sept. 29, 1959, Ser. No. 843,075 6 Claims. (Cl. 106287)This invention relates to new compounds suitable as softeners fortextile materials and more particularly to new compounds which may becharacterized as being suitable for use as rewettable softeners fortextile materials. It further relates to the methods of preparing suchcompounds, their use on textile material and the textile materialsfinished therewith.

' In the course of their manufacture and finishing, cotton and rayontextiles are usually subjected to various heat treatments. Often thetextile materials are coated or impregnated with fillers such as starch,gum tragacanth, gum ghatti, dextrines and the like, in order to impartbody to the cloth. I

Frequently, however, these treatments result in the production of arelatively stitf'fabric which is harsh to the feel and less desirablecommercially than fabrics possessing a soft hand. As a result theindustry has resorted to the use of several types of compounds for thesoftening of finished fabrics and in the case of rayon textile materialsfor imparting thereto increased lubricity.

Among the compounds hitherto employed by the art have been sulfonatedhydrocarbons, waxes, stearates, and sulfated oils such as cottonseedoil, peanut oil, coconut oil and similar oil products. Additionally, inview of the competitive economics involved in textile manufacture,-someof the most widely employed softening agents have been sulfated and/orsulfonated tallow, and sulfated, and/or sulfonated monoand diglyceridesof tallow, cottonseed oil, coconut oil, peanut oil and other compoundscontaining the relatively longcarbon chain of the higher fatty acids.The presence of these materials even in small amounts in cotton andrayon textiles have resulted in an undesirable yellowing of the fabricsubsequent to the heating thereof.

This problem which has long plagued the textile finishing industry wasto a substantial measure overcome by the relatively non-yellowingproducts which are described in U.S. Patent No. 2,734,833, the subjectmatter of which is incorporated herein by reference. Softeners preparedin accordance with thedescription contained within the above referred topatent, result in the impartation of excellent softness, and relativelylittle yellowing, compared to that normally produced by the presence ofsulfated or sulfonated vegetable oils found in a majority of textilesofteners.

While such softeners are for the most part highly desirable, these andmany others currently employed in the finishing of textile materialstoday are characterized by lack of absorbency and rewetting propertieswhich make them less than wholly desirable. This comparative inabilityto absorb moisture-and to be rewetted is a serious deficiency in textilematerials particularly where the end useccntemplated is in towellingsuch as is found in terry cloth towels and the like.

While most softeners may be characterized. as nondurable (i.e. uponwashing or ordinary laundering are removed) with the vast majority ofsuch merchandise being prepared and packaged today, so as to be readyfor immediate consumer use, this inability to absorb moisture and to berewetted has been a constant source of complaint and aggravation in thetextile industry.

Accordingly, it is an object of the present invention to provide acomposition suitable for use as a softener which is characterized byimparting a soft relatively nonyellowing finish to textile materialshaving good absorbency and rewetting properties.

It is a further object of the present invention to provide a process forpreparing such a composition.

Still further objects of the present invention are to provide a methodfor treating textile material with such a composition, and textilematerials characterized by a ready rewettability, softness andabsorbency.

These and other objects and advantages of this invention will becomemore apparent from the detailed description thereof set forthhereinbelow.

The present invention constitutes an improvement over that disclosed andclaimed in US. Patent No. 2,734,833.

We have found that by modifying members of the class of compoundsdescribed and claimed therein by a comparatively simple procedure, thata softener characterized by as much as about 30% improvement inabsorbency and rewetting may be prepared.

In accordance with the present invention, a mixture comprised of:

(l) A bis-ester of sulfosuccinic acids with a. bi-molec-, ular quantityof a member selected from a group consisting of higher fatty acidglycerides, glycols, alcohols and mixtures thereof, and

(2) A mixed di-ester of sulfosuccinic acid, the mixed ester ofsulfosuccinic acid being one with a substantial monomolecular quantityof saturated aliphatic alcohols having from 4 to 10 carbon atomsinclusive, a substantial monomolecular quantity of a member selectedfrom the group of higher fatty. glycerides, glycols, alcohols andmixtures thereof.

Preferably the mixture of 1 and 2 as identified above is one in whichthe components are present in a molecular ratio of between 1:3 to 3:1(preferably 1:1) and still more preferably where the mixture is to beemployed as a rewettable softener, the components are sulfonated inaccordance with a procedure well-known in the art and (1) is a his(tallow acid glyceride monosodium sul: fosuccinate) and (2) is a mixed2-ethyl hexyl, tallow acid glyceride diester of monosodium sulfosuccinicacid) in which 1 and 2 are present in monomolecular ratios of 1:1.

In general the individual essential component of the mixture abovedescribed may be characterized by the following general formulas:

R0% i l-OR GET-C OaMe where R is a member selected from the groupconsisting of higher fatty acid glycerides (monoand diglycerides) higherfatty acid glycols, higher fatty alcohols and mixtures thereof, andpreferably where R is the mixed monoand di-glycerol ester of fatty acidsderived from beef tallow and where Me is a salt from cation in a groupconsisting of alkali metals and ammonium; and

RO--% i-01y am-o,

SO Me where R and Me are as set forth above and R is a saturatedaliphatic alcohol containing from 4 to 10 carbon atoms inclusive andpreferably is Z-ethyl hexanol.

The term higher fatty as employed herein with respect to glycerides,glycols and alcohols, refers to materials in pure 'mono'glycerides.

'which the fatty component is characterized by a carbon chain length offrom C to C inclusive and preferably from C to C inclusive. In generalthe higher fatty materials are preferably saturated and in the case ofand to the extent that they are derivable from animal and/or vegetableoils, these materials should not have a polyunsaturated content ofgreater than 15 By polyunsaturation it is meant the presence of morethan one unsaturated double bond per fatty unit.

As suitable source of animal and vegetable oils and fats for the higherfatty acid glycerides and glycols contemplated for this invention or forhigher fatty acids- .'Il1ese. oleaginous materials do not possess anysubstantial amount'of hydroxy acids and they contain less than about 15%by weight of polyunsaturated acids, havingrelatively low iodine values(the quantity of iodine in mg. absorbed by 1 gm. of oil under normalconditions); and basically possess a non-drying nature.

Hydrogenated oils which do not contain any interferinghydroxy groups(such as in castor oil) may be used, provided the polyunsaturation ofthe fatty acids therein isreduced to below the above-mentioned 15% valueand to correspondingly low iodine values. Such oils would include:hydrogenated cottonseed oil; hydrogenated corn oil; hydrogenated peanutoil; hydrogenated soya bean oil; hydrogenated sunflower seed oil;hydrogenated sesame oil;- hydrogenated kapok oil; hydrogenated rapeseedoil; hydrogenated tung oil; etc.

Although these oils and fats contain fatty acids having various carbonchain lengths, the chain length of particular use within the concepts ofthe present invention from the system and thereafter a mole of fumaricacid is added. Under suitable reaction conditions the fumaric acidcombines the two excess moles of the monoglycerides of the tallow fattyacids and a mixed ester of maleic and fumaric acid results. Thiscondensation product is then sulfonated by use of a bisulfite ormetabisulfite containing a cationic salt-forming substituent, such asany of the alkali metals or ammonium. Preferably, the sulfonation iscarried out by heating the bis-ester with an aqueous solution of alkalimetal or ammonium bisulfite or metabisulfite whereby the correspondingsalt is obtained directly.

l-i'e's inthe range of aboutflZ to about 20 carbon atoms,

with16-l8 being the preferred range.

It is, of course, to be understood that selected fatty acids, such asstearic acid, lying in the preferred range of carbon-chain length, andpossessing. the properties characteristics noted above, may also beused.

It is not essential that the sulfosu'ccinic acid bis-ester be thereaction product resulting from the use of 100% A mixture ofmonoglycerides and diglycerides 'is normally commercially available andit has been found that a molar ratio of I-these two constituents withinthe range of about 5095% 0f monoglyceride and about 505% of diglycerideis well adapted for application to the principles of the presentinvention. The presence of diglycerides in greater proportions thanabout 50%, however, undesirably decreases the water solubilitycharacteristics of the compound and is to be avoided.

As an -example of higher fatty acid glycols the following areillustrative: diethylene glycol monostearate, diethylene' glycolmonolaurate, polyethylene glycol 200 monooleate, and the like.

As examples of fatty alcohols the following are illustrative: stearyl'alcoholcommercial grade, myristyl alcohol-commercial grade, laurylalcohol-+c0mmercial grade, and the like. I

The composition of this invention may be prepared by separatelypreparing the essential components, those materialscorresponding to thegeneral formulas set forth hereinabove and blending and by preparing theessential Alternatively, maleic anhydride may be reacted with an equalor substantially equal molecular quantity of, for example, tallow acidmonoglyceride and the resulting maleate reacted with a suitablesaturated aliphatic alcohol such as 2-ethy1 hexanol. The resultingproduct is thereafter reacted with sodium sulfite and sodium bi sulfiteto prepare a mixed ester of monosodium sulfosuccinate. This material isthen blended or mixed with a material such as is contemplated by generalformula 1 above.

The mixture forming the composition of this invention may be applied totextile material by employing conventional textile processing equipment(pad mangle, dye-beck and package machine) from aqueous solutions inconcentrations suflicient to deposit from between 0.25 to about 2.0%solids on the weight of the material after drying. Cellulosic fabrics sotreated exhibit excellent handling and draping qualities and are readilyrewetted by. water or aqueous solutions as required in compressiveshrinkage processes for dimensional stabilization or in finishes fortowellings and other absorbent fabrics.

In order to illustrate the present invention, the following examples aregiven primarily by way of illustration. No details or enumerationscontained therein should be construed as limitations on the presentinvention except insofar as pertaining to the present claims. All partsand percentages are by weight unless otherwise indicated.

EXAMPLE 1 g. (1 mole) of 2-ethyl hex-anol were reacted with 98 g. (1mole) of maleic anhydride at 85-90 C. in a closed vessel equipped withwater-cooled reflux condenser and agitator, until the acid value reached.239 (5 hours). Yield was 228 g.1(1 mole) of mono-Z-ethyl hexyl maleate.To this quantity, in the same vessel, was added 1,034 g. (3 moles) ofthe monoglyceride of tallow fatty acids and .226 g. of xylene. 18 g. :(1mole)v of water was removed from the. system by azeotropic distillationat 170? C. (3 /2 hours). 116 g. (1 mole), of fumaric acid was addedslowly and azeotropic distillation continued forlO hours at 170 C. untilan additional 36 g. 2 moles) of water were removed, (Acid value: 14.)

Xylene was removed by distillation under vacuum C. at 10 mm. Hg). Yieldwas 1300 g. of mixed 2-ethy1' hexyl and tallow acid monoglyceride estersof maleic and fumaric acids.

To 1250 g. of the above mixed esters were added 309 g. water, 51 g.sodium sulfite, 121 g. sodium bisulfite I and g. isopropanol. Thismixture was reacted at 86 C. under reflux for 6 hours. Yield was 1875 g.of a water dispersible material containing 76.5% real mixed 2-ethy1hexyl and tallow acid monoglyceride sodium sulfosuccina-tes.

, 1 EXAMPLE 2 400 g. (1.16 mole) of tallow acid monoglyceride was mole)of water was removed (acid value=14). Xylene was removed by distillationunder vacuum (150 C. at mm. of Hg). Yield was 630 g. of 2-ethy1 hexyl,tallow acid monoglycen'de maleate.

600 g. (1.08 mole) of above ester were refluxed with 36 g. of sodiumsulfite, 68 g. of sodium bisulfite, 78 g. isopropanol and 156 g. ofwater at 8688 C. for 5 hours. Yield was 930 g. of a water dispersiblepaste containing 76% of real 2 ethyl hexyl, tallow acid monoglyceridemono sodium sulfosuccinate.

50 g. of the product above was blended with 38 g. of his (tallow acidmonoglyceride) sodium sulfosuccinate and 12 g. of water to form a waterdispersible paste useful as a rewettable softener for cellulosicfabrics.

EXAMPLE 3 v This procedure is the reverse of that employed in Example 2.Mono-2-ethyl hexyl maleate was prepared, re-

acted with tallow and monoglyceride to form the mixed ester. This esterwas sulfonated and blended with an equal weight (real basis) of bis(tallow acid monoglyceride) sodium sulfosuccinate.

In order to demonstrate the superiority of the rewettable softener ofthis invention over those commercially available and typical of theprior art, the below comparative 'data has been assembled.

" ABSORBENCY A x 6 inch specimen of towel fabric weighted at one end, issuspended with the weighted end immersed to a depth of one inch indistilled water containing a watersoluble dyestutf. The capillary riseof the colored liquid in the fabric is observed at intervals. The heightat the end of two minutes compared with that in untreated towellingsimilarly tested is the percent absorbency.

SEWABILITY This test is a measurement of the lubricating properties ofthe finish. It is made on a harsh fabric of heavy construction(sulfur-dyed twill) to simplify the determination.

A 12" seam is sewn through four layers of the fabric under test in thewarp direction using a high speed sewing machine (4000 stitches perminute) equipped with a No. 19 needle at 16 stitches per inch. A 3"length of the seam is then ravelled to expose the yarns traversed by theseam and the number of broken filling ends in the third layer of fabriccounted. Best sewability, expressed as average number of breaks perinch, is indicated by minimum yarn breakage.

SOETNESS RATING- The relative softness or handling characteristics of ITable I EVALUATION OF SOFTENERS FOR TOWEL FINISHING Relative softnessYellowing, Percent Ratings Reflectance Ab- Sewing,

' sorbency Rewetting Sulfur Ratio of On Terry (secs) Dyed SoftenerApplied Solids 0n Seorch- Accele- Towel, Denim Twill,

Applied Terry On lng, rated Percent Loom Breaks] Towel- Cotton 30 secs.Storage, of Goods Inch ing Percale at 72 Hrs. Untreated 400 F. at 95 C.

Softener A 1 1 1 94 88 mogg than 15 1 Softener B 1 2 2 94. 5 88 84 14 2Mixture:

Softener A/bis(2ethyl hexyl) mono 1. 3 3 3 92 87. 5 84 4 29 sodiumsulfosucclnate 1.2/1 solids rat 0. Untreated 0 4 4 95 90 100 H1258 than32 In the applications, the softeners were padded onto towelling in thesolids indicated in Table l and thereafter the towelling was dried for15 minutes at 225 F. temperature.

In the comparative work reported in Tables 1 and 2 hereinbelow, thetests referred to therein are conducted as follows:

YELLOWING Searching-A specimen of the treated fabric is placed betweentwo metallic plates maintained at 400 F. for 30 seconds (Suder scorchtester). The reflectance of blue light (470 m from the scorced area isthen measured with any suitable instrument and expressed as percent ofthe reflectance from a magnesium carbonate standard.

Accelerated st0rage.A specimen of the treated fabric is enclosed in atightly sealed jar containing 0.25 ml. distilled water and stored for 72hours at 95 C. The reflectance of blue light (470 m from the fabricsurface is then measured with any suitable instrument and expressed asabove.

Table I hereinbefore demonstrates that Softener B the softener of thisinvention, is substantially superior with respect to softness comparedwith mixtures of Softener A andbis-(Z-et-hyl hexanol) monosodiumsulfosucoinate, and was superior with respect to yellowing by either ofthe tests identified in Table I. Further, Table I demonstrates thatSoftener B is markedly superior with respect to absorbency, whencompared with Softener A and is characterized by excellent sewabilitywith respect to either Softener A or the mixture.

A further evaluation of mixtures of Softener A and bis-(Z-ethyl hexanol)monosodi-um sulfosuccinate was conducted in order to demonstrate thatsuch mixtures are not the equivalent of such softeners as Softener B.

In this comparison, two mixtures of Softener A and the above referred tomonosodium sulfosuccinate were prepared and applied at the solidsindicated in Table II below. The finished towelling was then dried for15 minutes at 225 F. temperature. The results appear in Table I I below.

Table II EVALUATIONOF SOFTENER A/BIS-(Z-ETHYL HEXYL) MONO 'SODIUM' SULFOSUOCINATE MIXTURES FOR TOWEL FINISHING Table II demonstrates thatthe lower the mono sodium sulfosuccinate content, the poorer theabsorbency and therefore a solids ratio of approximately 9-10 to 1,which would be typical of a 2-ethyl hexyl content in the softeners ofthis invention (see Example 1), would be markedly inferior in absorbencyto the softeners of this invention. While the present invention andcompositions described therein have been limited to softeners of thetype contemplated by this invention, it should be kept in mind that suchcompositions may contain other materials as for example stabilizers,additional softeners'or textile modifying agents, lubricants, and thelike.

We claim:

1. A mixture consisting essentially of (1) a bis-este of sulfosuccinicacid with a substantially bi-molecular quantity of a member selectedfrom the group consisting of higher fatty acid glycerides, higher fattyacid glycols,

higher fatty acid alcohols and mixtures thereof, said higher fattyradicals being characterized by a carbon chain length of from C to Cinclusive and (2) a mixed di ester of sulfosuccinic acid with asubstantially mono molecular quantity of saturated. aliphatic alcoholshaving from 4 to carbon atoms inclusive and a substantially monomolecular quantity of a member selected from the group consisting ofhigher fatty acid glycerides, glycols, alcohols and mixtures thereofsaid higher fatty radicals being characterized by a carbon chain lengthof from C to C inclu'sive said (1) and (2) being present in a molecularratio of about 1:3 to about 3:1, respectively.

.2. A'mixture according to claim 1 in which (1) and (2) are presentinmolecular ratio of 1:.-1. 3. A mixture according to, claim 1 in which(1) and (2) are sulfonated.

4. A mixture according toclaim 3 in which (1) is a bis (tallow acidglyceride) mono sodium sulfosuccinate and (2) is a mixed Z-ethyl hexyl,fallow acid glyceride di-ester of monosodium sulfosuccinic acid.

5.A method of treating textile materials which com succinic acid with asubstantially bi-molecular quantity of a member of the group consistingof higher fatty acid glycerides, higher fatty alcohols and mixturesthereof, said higher fatty radicals being characterized by a carbonchainlength of from C to C inclusive and (2) a mixed di-ester of:sulfosuccinic acid with a substantially monomolecular quantity ofsaturated aliphatic alcohols having from 4 to 10 carbon atoms inclusiveand a substantially mono-molecular quantity of a member selected fromthe group consisting of higher fatty glycerides, glycols, alcohols andmixtures thereof said higher fatty radicals being characterized by acarbon chain length of from C to C inclusive said (1) and (2) of saidrewettable softening agent being present in a molecular ratio of about1:3 to about 321, respectively. I

6. A textile material characterized by a softness of hand and readyrewettability comprising a textile material having distributed thereon,(1) a bis-ester of sulfo succinic acid with a substantially bi-molecmlarquantity of a member of the group consisting of higher fatty acidglycerides, higher fatty acid glycols, higher fatty alcohols andmixtures thereof, said higher fatty radicals being characterized by acar-hon chain length of from C to C inclusive and (2) a mixed di-esterof sulfosuccinic acid with a substantially mono molecular quantity ofsaturated aliphatic alcohols having from 4 to 10 carbon atoms inclusiveand a substantially mono molecular quantity of a member selected fromthe group consisting of higher fatty glycerides, glycols, alcohols andmixtures thereof said higher fatty radicals being characterized by acarbon chain length of from C to C inclusive said (1) and (2) beingpresent in a molecular ratio of about 1:3 to about 3:1, respectively.

References Cited in the file of this patent UNITED STATES PATENTS2,637,663 Thurston May 5, 1953 2,734,833 Thurston Feb. 14, 19562,761,795 Carncs Sept. 4, 1956 2,826,514

Schroeder Mar. 11, 1958

1. A MIXTURE CONSISTING ESSENTIALLY OF (1) A BIS-ESTER OF SULFOSUCCINICACID WITH A SUBSTANTIALLY BI-MOLECULAR QUANTITY OF A MEMBER SELECTEDFROM THE GROUP CONSISTING OF HIGHER FATTY ACID GLYCERIDES, HIGHER FATTYACID GLYCOLS, HIGHER FATTY ACID ALCOHOLS AND MIXTURES THEREOF, SAIDHIGHER FATTY RADICALS BEING CHARACTERIZED BY A CARBON CHAIN LENGTH OFFROM C12 TO C20 INCLUSIVE AND (2) A MIXED DIESTER OF SULFOSUCCINIC ACIDWITH A SUBSTANTIALLY MONO MOLECULAR QUANTITY OF SATURATED ALIPHATICALCOHOLS HAVING FROM 4 TO 10 CARBON ATOMS INCLUSIVE AND A SUBSTANTIALLYMONO MOLECULAR QUANTITY OF A MEMBER SELECTED FROM THE GROUP CONSISTINGOF HIGHER FATTY ACID GLYCERIDES, GLYCOLS, ALCOHOLS AND MIXTURE THEREOFSAID HIGHER FATTY RADICALS BEING CHARACTERIZED BY A CARBON CHAIN LENGTHOF FROM C12 TO C20 INCLUSIVE SAID (1) AND (2) BEING PRESENT IN AMOLECULAR RATIO OF ABOUT 1:3 TO ABOUT 3:1, RESPECTIVELY.